Rechargeable flashlight and battery assembly for single-handed intermittent and continuous operation

ABSTRACT

A rechargeable flashlight is also provided. The flashlight includes a housing having a battery compartment and a light source adjacent a first end of the housing. A rechargeable lithium-ion battery provides power for the flashlight. A controller circuit serially connected with the battery is operable to control the flow of electricity to and from the battery. Specifically, the controller circuit is operable to disconnect the lithium-ion battery cell from the light source in response to the charge in the lithium-ion battery depleting below a pre-determined lower threshold. The control circuit is further operable to disconnect the lithium-ion battery cell from electrical connection with the first charging contact when the lithium-ion battery is connected with a battery charger and the charge in the lithium-ion battery reaches a pre-determined upper threshold.

PRIORITY INFORMATION

This application is a continuation of U.S. application Ser. No.10/753,216, filed Dec. 19, 2003, which is set to issue on May 22, 2007as U.S. Pat. No. 7,220,013.

BACKGROUND

Rechargeable flashlights are known in which a flashlight containing arechargeable battery is provided with a compatible charging unit whichboth holds the flashlight and charges the battery when the flashlight ispositioned therein. As described in U.S. Pat. No. 5,432,689, it isdesirable to provide such a flashlight and charger assembly wherein thebody of the flashlight is not used as a conduction path for either sideof a lamp circuit, so that mating parts of the flashlight may beprovided with an anodized, enamel, or other finish, and do not requirere-machining in order to provide a conductive path between finishedmating parts.

In the use of flashlights by armed personnel, such as by policemen, itis desirable to provide a flashlight that can be gripped andintermittently actuated with a single hand. For example, it is desirableto provide an actuator at the rear end of such a flashlight, so that theflashlight may be gripped with the fingers of one hand, and the actuatorcan be operated by the thumb of the same hand. However, locating aswitch mechanism at the rear end of the flashlight while maintaining aconstruction which does not utilize the body of the flashlight as aconducting member, and in which a continuous connection is maintainedbetween the battery terminals and a pair of external charging contactspresents design difficulties for which no solution is suggested in theabove-referenced U.S. Pat. No. 5,432,689.

SUMMARY OF THE INVENTION

In accordance with one aspect of the present invention, a rechargeableflashlight is provided in which a the flashlight is charged by twocharging contacts located on or near the forward end of the flashlight.The flashlight is configured to provide intermittent single-handedoperation of the lamp circuit, and optionally to provide continuousswitched operation. Continuous electrical contact between respectivebattery terminals located at the forward end of a battery assembly, anda pair of external charging contacts, is maintained by a configurationof springs mounted to a connection member located in the forward end ofthe flashlight. The connection springs extend rearwardly from theconnection module to maintain contact with the battery terminals, whilealso urging the battery assembly rearwardly within the flashlight. Aspring loaded plunger located in the connection module is also biasedrearwardly, and aligned with a terminal of the battery assembly and withan electrical contact on a lamp base. The tail of the flashlightincludes a slide member, having an actuation surface at the rear of theflashlight, for urging the battery assembly in the forward directionwithin the flashlight barrel, and further urging the plunger toward thelamp base contact. Hence, intermittent operation of the lamp isprovided. In a preferred embodiment, continuous operation of the lamp isprovided by configuring the tail assembly to hold the slide member at aforwardly-advanced position in the rear of the barrel.

In accordance with another aspect of the present invention, arechargeable flashlight is provided in which the flashlight includes ahousing and a light source adjacent a first end of the housing. Therechargeable battery is a lithium-ion battery. A controller circuitserially connected with the battery is operable to control the flow ofelectricity to and from the battery. For instance, the controllercircuit is operable to disconnect the lithium-ion battery cell from thelight source in response to the charge in the lithium-ion batterydepleting below a pre-determined lower threshold The controller circuitis also operable to disconnect the lithium-ion battery cell fromelectrical connection with the first charging contact when thelithium-ion battery is connected with a battery charger and the chargein the lithium-ion battery reaches a pre-determined upper threshold.

BRIEF DESCRIPTION OF THE DRAWINGS

The foregoing Summary, as well as the following Detailed Description,will be best understood in connection with the attached drawings inwhich:

FIG. 1 is a perspective view of a flashlight and charger in accordancewith the present invention.

FIG. 2 is a perspective view of the flashlight of FIG. 1 removed fromthe charger.

FIG. 3 is a cross-sectional view of the flashlight of the invention.

FIG. 4 is an exploded view of a connection module located within thehead of the flashlight of FIG. 3.

FIG. 5 is a cross-sectional view of the connection module of FIG. 4.;and

FIG. 6 is an exploded view of a battery assembly utilized in theflashlight of FIG. 3.

DETAILED DESCRIPTION OF THE DRAWINGS

Referring now to FIG. 1, the flashlight 10 is shown engaged within acharger 12. The charger 12 is substantially identical in constructionwith the charger shown in U.S. Pat. No. 5,432,689, which is incorporatedby reference herein in connection with the charger assembly. Referringto FIG. 2, the flashlight 10 comprises a head assembly 14 connected withthe forward end of a barrel 16. A tail assembly 18 is connected with therear end of the barrel. A guide plate 13 is positioned on the exteriorof the head assembly 14 for guiding the flashlight into the charger.Positioned within the guide plate are a pair of charging contacts 40 and38, for mating with compatible connecting contacts located in thecharger.

The forward end of the flashlight is formed by a facecap assembly 20which is rotatably mounted at the forward portion of the head assembly14. Referring now to FIG. 3, the facecap assembly 20 holds a circularlens 22 and a reflector 24 within a cylindrical carrier 26. The terminalrear portion of the reflector has threads 28 formed thereon to provide athreaded connection with a forward portion of the head assembly 14. Theouter surface of the facecap assembly 20 is preferably knurled toprovide a gripping surface thereon, so that the facecap assembly 20 canbe rotated to move the facecap assembly 20 in the forward or reversedirections upon the threads 28 to vary the focus of the flashlight. Ano-ring is positioned within a chase 30 formed about the outer surface ofthe forward end of the head assembly 14 to provide a fluid seal betweenthe head assembly 14 and the facecap assembly 20.

A connection module 32 is positioned within the head assembly 14.Described in greater detail hereinbelow, the connection module 32supports a lamp holder 34, in which a bi-pin lamp 36 may be inserted asshown. The The connection module 32 provides continuous electricalconnection between battery terminals 44 and 46 and respective ones of apair of contact screws 38 and 40, which extend from the exterior surfaceof the flashlight 10 through a charger alignment plate 42 and into theconnection module 32 positioned in the interior of the head assembly 14.The connection module further provides a switchable electricalconnection between the battery terminals 44 and 46 and respectiveterminals of the bi-pin lamp 36.

The rear portion of the head assembly 14 is press-fit for permanentengagement onto the forward end of the barrel 16. A battery assembly 48is housed within the barrel 16. As described further hereinbelow, thebattery assembly has respective negative and positive contacts 44 and 46both positioned at the forward end thereof within the barrel 16.

A tail assembly 18 is connected with the rear of the barrel 16. The tailassembly comprises a cylindrical tail housing 50 having threads 52formed about the exterior forward end thereof to provide a threadedconnection with the interior rear portion of the barrel 16. Acylindrical slide member 54 is slidably positioned within the tailassembly 18. The forward end of the slide member 54 is enlarged so thatthe slide member is captured against rearward movement by an reduceddiameter rim 56 formed in the tail housing 50. The slide member 54 ispreferably hollow to provide storage space for a spare lamp (not shown),and is closed at the rear end thereof. A semi-permeable filter member 58is positioned within a hole extending through the rear wall of the slidemember 54, in order to vent gases from within the flashlight.

More views of the connection module 32 are shown in FIG. 4 and FIG. 5.The connection module 32 comprises two clamshell housing pieces 60 and62. The housing pieces 60 and 62 are formed to capture severalconductive components therein as follows. The lamp base 34 fits within arecess formed between the two housing pieces 60 and 62. The lamp base ispreferably composed of a liquid crystal polymer material havingrelatively high heat resistance to act as a barrier to heat generated bythe lamp and to provide a heat shield for the connection module. Theconnection module 32 may be made of an acetol polymer material such asDELRIN, which provides suitable mechanical performance for moving partssituated therein. On the rear surface of the lamp base 34, there isprovided a conductive contact member 64 for the positive terminal of thelamp circuit. Extending from one side of the lamp base 34, and heldwithin a recess formed in the housing pieces, a negative contact member66 extends within the connection module toward the side of the module. Aterminal portion of the contact member is bent upward and has areceiving ring formed therein to connect with the negative contact screw40. A conical spring 68 is positioned to extend from the rear of theconnection module 32 to connect with the negative terminal of thebattery assembly. The conical spring 68 has a contact arm portion 70that runs through the connection module to connect with the negativecontact member 66. When the flashlight is assembled with the batteryassembly in place, continuous compressive contact is maintained betweenthe negative terminal at the forward end of the battery and the conicalspring 68, so that a continuous charging connection is provided betweenthe negative contact screw and the negative terminal of the battery.

A positive contact member 72 has a ring portion for connecting with thepositive contact screw. The positive contact member is positioned in theconnection module and extends to provide a circular contact ring 74which is aligned within the connection module at a position to the rearof the lamp base 34. A plunger cavity 76 is formed in the rear of theconnection module between the clamshell pieces 60 and 62. A plunger 78is slidably captured in the connection module by a rim 80 formedthereon. A rear portion of the plunger 78 extends out of the rear of theconnection module. Within the plunger cavity 76, a spring 82 iscompressed between the rim 80 and the rear of the circular contact ring74. Outside of the plunger cavity, the rear of the plunger 78 connectswith a spring 84 that extends rearwardly from the connection module toconnect with the positive terminal of the battery assembly. The spring84 is thus maintained in continuous compressive contact with thepositive terminal of the battery, so that at all times a conductive pathis provided between the positive terminal of the battery and thepositive charging contact on the exterior of the flashlight.

The plunger 78 has a tip portion aligned with the rear of the lamp base34, and the positive lamp contact thereon. The plunger is urgedrearwardly within the plunger cavity 76, by the spring 82, so that in afirst position, the tip of the plunger 76 is maintained out of contactwith the positive lamp contact. Referring again to FIG. 3, it can beseen that by depressing the slide member 54 into the rear of the tailassembly, the slide member 54 urges the battery assembly forward withinthe barrel 16. Thus, when the slide member 54 is so depressed, themovement of the battery assembly compresses both springs 84 and 82, tourge the tip of the plunger into contact with the positive lamp contacton the rear of the lamp base. The lamp may therefore be intermittentlyswitched on and off by holding the flashlight in the fingers of onehand, and depressing the slide member with the thumb of the same hand.

To maintain the lamp in a continuous “on” condition, the tail housing 50may be rotated into the rear of the barrel on the threads 52, so thatthe springs 84 and 82 are again compressed to move the plunger tip intocontact with the positive lamp contact. Thus, the configuration hereindescribed provides intermittent or continuous switching of the lamp.

The battery assembly is shown in an exploded view in FIG. 6. Thepreferred cell for the battery is a Lithium-ion rechargeable cell. Thebattery assembly provides two battery terminals 108 and 101 exposed atthe forward end thereof in a concentric arrangement as viewed from theforward end. A battery protection circuit disconnects the Li-ion cellfrom the lamp circuit from further charging when the cell is fullycharged, and also disconnects the cell from the lamp circuit when thecharge is depleted below a predetermined threshold. The battery assemblyis constructed as follows. A Li-ion rechargeable cell 90 is firstprovided with a shrink-wrap insulating jacket 92. A conductive strap 94is connected with the cell contact at the negative end of the cell andwith a protection circuit board 96. An insulating spacer 98 ispositioned between the rear of the cell 90 and the forward side of thecircuit board 96. A length of insulating tape 99 is applied to one sideof the jacket 92, and a conductive strap 100 is connected with thecircuit board 96 at the rear of the assembly, and extends to the forwardend of the assembly for connection to the positive cell contact at theforward end. The forward end of the strap 100 extends across thepositive cell contact, and then connects with a positive battery contactterminal member 101. The strap 100 is bent backwards, and an insulatingspacer 102 is positioned between the positive contact of the cell andthe positive contact terminal member.

On the other side of the jacket 92, another strap 104 is connected tothe negative cell contact, and is positioned over an insulating strip106 positioned on that side of the jacket. The forward end of the strap104 is connected to an annular negative battery contact terminal 108 atthe forward end of the cell. The annular negative terminal 108 ispositioned on an insulating member 110 which has a hollow cylindricalvertical extension formed therein for guiding the spring into contactwith the positive contact terminal 101.

A disk-shaped low-profile housing 112 is placed over the rear side ofthe protection circuit, and an insulating spacer 114 is placed on therear side of the housing, to mechanically protect the protectioncircuit. Finally, the sheathed cell, strap, and protection circuitarrangement is enclosed in a rigid plastic shell formed by shell members116 and 118. The shell is closed at the rear end, and is open at theforward end to permit the springs to connect with the respectivecontacts. An adhesive label 120 may be placed over the shell to hold theshell members together.

The terms used here and above are intended by way of exemplarydescription, and not of limitation. There is no intent for such terms ofdescription to otherwise limit the scope of the appended claims.

1. A flashlight assembly, comprising: a housing having a batterycompartment; a lamp head providing a light source, connected with thehousing; a lithium-ion rechargeable battery cell positionable within thecompartment; a control circuit operable to control charging anddischarging of the battery cell; a battery charger operable toelectrically engage the battery cell to re-charge the battery cell;wherein the control circuit is operable to disconnect the lithium-ionbattery cell from the light source in response to the charge in thelithium-ion battery cell depleting below a pre-determined lowerthreshold, and wherein the control circuit is operable to disconnect thelithium-ion battery cell from electrical connection with the batterycharger when the lithium-ion battery is connected with the batterycharger and the charge in the lithium-ion battery reaches apre-determined upper threshold.
 2. The flashlight system of claim 1wherein the upper threshold corresponds to the lithium-ion battery beingfully charged.
 3. The flashlight system of claim 1 comprising a batteryhousing for housing the battery cell and a protective housing separatefrom the battery housing to protect the control circuit.
 4. Aflashlight, comprising: a housing having a battery compartment; a lightsource adjacent a first end of the housing; a first charging contact; asecond charging contact; a rechargeable lithium-ion battery operable tostore a charge and configured to be positioned in the batterycompartment, wherein the battery has a first contact and a secondcontact for charging the battery, wherein the first contact of thebattery is electrically coupled with the first charging contact and thesecond contact of the batter is electrically coupled with the secondcharging contact, and wherein the light source is electrically coupledwith the first and second contacts of the battery; a controller circuitserially connected with the first battery contact, wherein thecontroller circuit is operable to disconnect the lithium-ion batterycell from the light source in response to the charge in the lithium-ionbattery depleting below a pre-determined lower threshold, and whereinthe control circuit is operable to disconnect the lithium-ion batterycell from electrical connection with the first charging contact when thelithium-ion battery is connected with a battery charger and the chargein the lithium-ion battery reaches a pre-determined upper threshold. 5.The flashlight of claim 4 wherein the controller is separate from thelithium-ion battery.
 6. The flashlight of claim 4 wherein the first andsecond contacts are configured to cooperate with contacts of the batterycharger for charging the battery.
 7. The flashlight of claim 4comprising a first electrical path extending from the rearward end ofthe flashlight to a forward end of the flashlight and in electricalcommunication with the light element, wherein the first electrical pathincludes the first battery contact.
 8. The flashlight of claim 7comprising a second electrical path extending from the rearward end ofthe flashlight to a forward end of the flashlight and in electricalcommunication with the light element, wherein the second electrical pathincludes the second battery contact.
 9. The flashlight of claim 4comprising a switch for controlling operation of the flashlight, theswitch being positioned adjacent a rearward end of the housing, remotefrom the first end of the housing.
 10. A flashlight, comprising: ahousing having a battery compartment; a lamp head connected to a firstend of the housing, wherein the lamp head comprises a light element; arechargeable lithium-ion battery operable to store a charge andconfigured to be positioned in the battery compartment, wherein thebattery has a first contact and a second contact; a first electricalpath extending substantially the length of the battery compartment fromthe rearward end of the battery to the first end of the housing; asecond electrical path extending substantially the length of the batterycompartment from the rearward end of the battery to the first end of thehousing; a switch for controlling operation of the flashlight, theswitch being positioned adjacent a rearward end of the housing, remotefrom the first end of the housing; a circuit board comprising acontroller circuit serially connected with the battery, wherein thecontroller circuit is operable to disconnect the lithium-ion batterycell from the light element in response to detection of a firstcharacteristic and further operable to disconnect the lithium-ionbattery cell from a separate charging device in response to detection ofa second characteristic that is different from the first characteristic,wherein neither the first nor the second characteristic compriseoperation of the switch.
 11. The flashlight of claim 10 wherein thefirst characteristic comprises the charge in the lithium-ion batterydepleting below a pre-determined lower threshold.
 12. The flashlight ofclaim 11 wherein the second characteristic comprises the charge in thelithium-ion battery reaching a pre-determined upper threshold while thebattery is in electrical connection with a battery charger.
 13. Theflashlight of claim 10 wherein the switch is an axially displaceableswitch biased in a rearward direction.
 14. The flashlight of claim 10wherein the battery comprises a housing and the flashlight comprises ahousing separate from the battery housing and configured to house andprotect the control circuit.